A restaurant worker who was "obsessed" with his boss has been convicted of brutally attempting to murder her partner.
Alexander Cornell, 27, became infatuated with Piotrowski's girlfriend, then stabbed him in Parkway car park in Bury St Edmunds in Suffolk last year.
Ipswich Crown Court heard that Cornell, of Britannia Road, Ipswich, had become obsessed with his manager at a restaurant in Ipswich, despite her being in a committed relationship with Mr. Piotrowski.
The court heard that Cornell - who had worked with Mr Piotrowski's girlfriend for five years - began swamping her with gifts and following her to the gym.
Despite her telling him there was no chance of a relationship, and changing her gym membership several times, Cornell continued to stalk her - changing his gym membership each time she did so he could turn up while she was working out, said Suffolk Police.
He even saved a photo of her face as the background on his Apple watch.
Just before 2.30pm on Monday, 4 July, his obsession turned deadly when he stabbed Mr. Piotrowski in the back and neck to get him out of the picture, said Suffolk Police.
Cornell was arrested later the same day and his victim was taken to the West Suffolk Hospital, where he received treatment for deep knife wounds.
Det Con Guy Mitchell of Suffolk Police said: "The victim’s partner found the best course of action was to ignore his behaviour as she believed any attention would only encourage him.
"Cornell also had the 39-year-old woman’s photo as his background for his Apple watch, despite being confronted about it and promising to change it.
"This was an extremely nasty, violent and pre meditated attack on the man and would have been extremely frightening to have Cornell attack him from behind.
"The victim is very lucky that his injuries were not ultimately fatal."
Cornell will be sentenced on 9 March.
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